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   <title>logm :: Functions (Quaternion Toolbox Function Reference)
</title><link rel="stylesheet" href="qtfmstyle.css" type="text/css"></head><body><h1>Quaternion Function Reference</h1><h2>logm</h2>
<p>Matrix logarithm<br>(Quaternion overloading of standard MATLAB&reg; function)
</p>
<h2>Syntax</h2><p><tt>X = logm(Y)</tt></p>
<h2>Description</h2>
<p>
<tt>logm(X)</tt> computes the matrix logarithm of a quaternion matrix.
The algorithm used is based on calling the MATLAB&reg; <tt>logm</tt> function
on an adjoint matrix, and is therefore not accurate for larger matrices.
It may also fail for some quaternion matrices.
The accuracy may be checked using the <tt>expm</tt> function.
</p>

<h2>See Also</h2>MATLAB&reg; function: <a href="matlab:doc logm">logm</a><br>QTFM functions: <a href="expm.html">expm</a>, <a href="adjoint.html">adjoint</a>, <a href="unadjoint.html">unadjoint</a><br>
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